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ORIGINAL ARTICLE
Year : 2016  |  Volume : 60  |  Issue : 3  |  Page : 188-194  

Assessment and comparison of pregnancy outcome among anaemic and non anaemic primigravida mothers


1 Medical Scientist, Department of Obstetrics and Gynaecology, All India Institute of Medical Sciences, New Delhi, India
2 Professor and Head, Department of Obstetrics and Gynaecology, All India Institute of Medical Sciences, New Delhi, India
3 Assistant Professor, Department of Obstetrics and Gynaecology, All India Institute of Medical Sciences, New Delhi, India
4 Medical Social Worker, Department of Obstetrics and Gynaecology, All India Institute of Medical Sciences, New Delhi, India
5 Scientist C, Indian Council of Medical Research, New Delhi, India

Date of Web Publication24-Aug-2016

Correspondence Address:
Dr. Rohini Sehgal
B-4/125, Safdarjung Enclave, New Delhi - 110 029
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0019-557X.189011

Clinical trial registration REF/2014/05/006962

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   Abstract 

Background: Primigravidas (PGs) are high-risk women and anemia in pregnancy is one of the commonest causes of maternal morbidity and mortality. Objectives: The study was conducted to assess impact of anemia on course and outcome of pregnancy in anemic (Hemoglobin 8-10.9 gm%) and nonanemic PGs. Methods: This prospective longitudinal study was conducted in All India Institute of Medical Sciences, New Delhi. PGs 20-30 years age, gestation age 16-18 weeks, hemoglobin >8 gm%, live singleton pregnancy, and no other medical illness were recruited after informed consent. The women were Grouped 1 and 2 if hemoglobin was ≥11 gm% and 8-10.9 gm%, respectively. Complete hemogram done at enrollment, 28-30 weeks of pregnancy and 6 weeks postdelivery. Obstetric outcome and presence of anemia postdelivery were compared between groups using Chi-square test and Fisher's exact test. Results: A total of 377 PGs were enrolled and obstetric outcomes studied in 179 (Group 1) and 149 (Group 2) excluding women who did not complete study. There was no statistically significant difference in baseline characteristics, antenatal complications, gestational age, mode of delivery, and neonatal outcome. At 28-30 weeks of gestation, in spite of iron supplementation higher percentage (64.4%) (P < 0.05) of anemic patients remained anemic. At 6 weeks postdelivery, 15.6% and 24.2% were anemic in Group 1 and 2, respectively (P > 0.05). The adverse postpartum events (7.6%) were seen more in anemic compared to nonanemic pregnant women (P < 0.05). Conclusions: Cautious approach required in postpartum period of anemic women though antenatal period is similar as nonanemic pregnant women.

Keywords: Anemia, obstetric and neonatal outcome, primigravida


How to cite this article:
Sehgal R, Kriplani A, Vanamail P, Maiti L, Kandpal S, Kumar N. Assessment and comparison of pregnancy outcome among anaemic and non anaemic primigravida mothers. Indian J Public Health 2016;60:188-94

How to cite this URL:
Sehgal R, Kriplani A, Vanamail P, Maiti L, Kandpal S, Kumar N. Assessment and comparison of pregnancy outcome among anaemic and non anaemic primigravida mothers. Indian J Public Health [serial online] 2016 [cited 2019 Sep 22];60:188-94. Available from: http://www.ijph.in/text.asp?2016/60/3/188/189011


   Introduction Top


Primigravida (PG), defined as a woman who conceives for the first time, is in a high-risk group. PGs are at significantly higher risk for prolonged first and second stage of labor, increased chances of fetal distress during labor and need for intensive monitoring as compared to the multigravidas. PGs are also at significantly increased risk for operative vaginal delivery and emergency cesarean section. [1] The chances of primary postpartum hemorrhage in PGs are found to be more, and perinatal morbidity is also increased in the group.

As per World Health Organization estimates (WHO) in India, about 58% of pregnant women are anemic and anemia is indirectly responsible for 20-40% of maternal deaths. [2] According to the WHO, anemia in pregnancy is present when the hemoglobin concentration in the peripheral blood is <11 gm%. Anemia in pregnancy is further divided into three grades, 10-10.9 gm% as mild anemia, 7-10 gm% as moderate anemia, and <7 gm% as severe anemia. [3] The prevalence of anemia in pregnancy as per National Family Health Survey-3 in India is as high as 58.7%. [4] The present study was conducted with the objective of to assess the impact of anemia on course and outcome of pregnancy in anemic (hemoglobin 8-10.9 gm%) and nonanemic PGs.


   Materials and Methods Top


This study is a part of a multicentric Indian Council of Medical Research (ICMR) task force study (CTRI REF/2014/05/006962) conducted in the Department of Obstetrics and Gynaecology, All India Institute of Medical Sciences, New Delhi, from February 2007 to September 2013. This study used nonprobability purpose sampling and had two groups - Group 1 and 2 consisting of nonanemic and anemic PGs (hemoglobin >11 gm% and 8-10.9 gm%) respectively. After enrollment depending on the hemoglobin status, the woman was grouped.

The present study was a prospective longitudinal study. The sample size was based on an expected outcome in the treatment schedules of daily versus weekly oral iron treatment among anemic women under the trial. In this present article, we have reported the findings of anemic and nonanemic women enrolled in our center.

Primigravid women aged between 20 and 30 years with a period of gestation 16-18 weeks and who had live singleton pregnancy on ultrasound (USG) were recruited in the study after taking informed consent. Inclusion criteria included PGs with or without mild to moderate anemia and with no other medical illness. The women with thalassemic gene disorders were excluded from the study at the time of enrollment.

All the enrolled women were dewormed in the second trimester at the start of the study. Women with severe anemia and fetal congenital anomalies detected on USG were excluded. Demographic and gestational status data were collected with the help of structured questionnaire from booked antenatal mothers at the time of enrollment. The follow-up was done at 4 weeks interval up to 32 weeks, 2 weeks interval up to 36 weeks, and then weekly till delivery. Routine antenatal care (ANC), dietary advice and investigations were carried out as per hospital practice. Complete hemogram was done at enrollment, between 28 and 30 weeks of pregnancy and 6 weeks postdelivery. To know impact of anemia on course and outcome of pregnancy in anemic and nonanemic women, obstetric outcome was compared between two groups in terms of antenatal complications, gestational age at delivery, mode of delivery, infant's birth weight, the presence of anemia postdelivery, and cesarean section rate. Neonatal outcome was compared between two groups in terms of birth weight, congenital anomaly, neonatal morbidity during hospital stay, and admissions in the Neonatal Intensive Care Units (NICSs).

Statistical analyses

The data were analyzed using Statistical package for Social Sciences (SPSS) IBM version 19.0.( Armonk, New York, IBM Corporation). Descriptive statistics such as mean, standard deviation, and range values were computed for quantitative variables. Continuous variables were tested using Kolmogorov-Smirnov test for normality assumption of the data. For approximate to normally distributed data, Student's t-independent test with equal variance assumed was used to see any significant difference between two groups. Frequency data across categories were compared using Chi-square/Fisher's exact test as appropriate. Whenever, the expected cell value was <5 in 2 × 2 table, Fisher's exact test was carried out. A probability level P < 0.05 was considered for statistical significance.


   Results Top


A total of 377 PGs were recruited with 211 nonanemic (Group 1) PGs (56%) and 166 mild to moderately anemic (Group 2) PGs (44.0%) in the 20-30 years age group, respectively. The lost to follow-up in Group 1 and Group 2 PGs was 32 (15.2%) and 17 (10.2%) respectively. Hence, the obstetric outcome was studied in 328 PGs with 179 and 149 women in Group 1 and 2, respectively as seen in Flow Chart 1.



The mean age, body mass index, education, age at menarche, menstrual cycle, age at marriage, and gestational age at delivery of the women was 24.20 versus 24.15 years (P = 0.851), 21.79 versus 21.15 (P = 0.065), 16.2 versus 16.02 years (P = 0.787), 13.93 versus 13.81 years (P = 0.689), 29.22 versus 29.57 days (P = 0.594), 23.11 versus 23.21 years (P = 0.836), and 269.91 versus 270.17 days (P = 0.833), respectively for Group 1 and 2, respectively. It was observed that the base-line characteristics were similar in both groups (P > 0.05).

As seen in [Table 1], about 64% and 60% of Group 1 and Group 2 patients did not report any event. Out of 36 women with pregnancy-induced hypertension (PIH), there was one case of PIH with HELLP, and 4 women had severe PIH/eclampsia, and all severe cases were in Group 1 (P = 0.04). In 26 women, there were two or more coexisting high-risk factors.
Table 1: Distribution of the different events during antenatal period in both groups


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Preterm (<37 weeks) delivery among Group 1 and Group two patients were 12.8% and 11.4% respectively (P = 0.692). The induced preterm deliveries in the Groups 1 and 2 were 8.7% 2/23 and 11.7% 2/17 respectively (P > 0.05). Spontaneous vaginal delivery in Group 1 and Group 2 was 89.9% and 87.3% respectively (P > 0.05). Mode of delivery and indications of lower segment cesarean section (LSCS) for the two groups of patients are presented in [Table 2]. There was a significant (P = 0.036) variation in the mode of delivery among the two groups of women.
Table 2: Mode of delivery and indications of lower segment cesarean section among the two groups of patients


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The postpartum period was uneventful in 303 PGs (92.4%). In Group 1, 3.9% (7/179) women had morbidity compared to 12.1% (18/149) in Group 2 (P = 0.005) [Table 3] and [Figure 1].
Figure 1: Comparison of postpartum events in the two groups of patients

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Table 3: Comparison of postpartum events in anemic versus nonanemic pimigravidas


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The percent of patients who received blood transfusion or blood products (BT) in Group 1 and Group 2 were 1.7% and 8.1% respectively (P = 0.007). The BT in the antenatal and postpartum period for Group 1 and Group 2 patients was 0.6% versus 1.3% and 1.1% versus 6.7%, respectively. The indication for BT in the majority was postpartum hemorrhage (8/15, 53.3%; Group 2-06) and the rest of the indications were retained placenta (2; Group 2-2), post-LSCS (1; Group 2-1) and dengue fever (2; Group 2-2), gestational hypertension with HELPP syndrome (1; Group 2-0), and prior to LSCS (1; Group 2-1) [Table 4].
Table 4: Blood transfusion or blood products in Group 1 and Group 2


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The incidence of intrauterine growth retardation (IUGR) was almost similar (7.3 vs. 8.0%, P = 0.06) in the two groups. There were two neonatal deaths, one each in both groups. The cause of death in Group 1 was baby with congenital heart anomaly and in Group 2, low birth weight (LBW) and IUGR baby with birth asphyxia. Of 328 neonates, 19 (10.6%) and 20 (13.4%) in Group 1 and 2 respectively were admitted to NICUs (P = 0.43) [Table 5].
Table 5: Distribution of neonatal outcomes in both groups


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   Discussion Top


PGs are important regarding the subsequent obstetrical performance. All the enrolled women were in the age group 21-30 years, the only high-risk factors being a PG and mild to moderate anemia in almost half. There is evidence that mildly anemic pregnant women if well compensated with iron therapy may have an uneventful obstetric outcome. The moderately anemic women need supervision because they may not be able to bear blood loss before or during labor and are more prone to infections. Substantial proportion of maternal deaths is due to the moderate anemia if associated with antepartum hemorrhage (APH), postpartum hemorrhage (PPH), PIH with sepsis a known risk factor for maternal mortality. [5]

This study observed 0.6% (2/328) spontaneous abortions less than reported 1-5% at 13-19 weeks' gestation with no difference between two groups. [6] The congenital anomalies detected were 1.5% similar to reported 1.28% in young PGs with no difference between anemic versus nonanemic groups. [7] More than one-third of PGs (38.1%) in this study developed a high-risk factor during ANC, and the percentage was almost similar in both nonanemic and mild to moderately anemic groups (63.7% versus 59.7%, respectively). However, most of the adverse factors observed were those where antenatal monitoring, planned and supervised labor and puerperium were able to prevent poor perinatal outcome and maternal morbidity.

PGs are known to be high-risk for PIH (8-10%) and associated medical complications such as gestational diabetes mellitus (GDM), thyroid disorders, and intrahepatic cholestasis of pregnancy have been reported as 1-7, 3.4, and 0.9%, respectively in Indian women in previous studies. [8],[9],[10],[11],[12] There was no difference in the incidence of PIH, GDM, thyroid disorders and ICP in normal versus PGs with Hb 8-10.9 gm%. Timely diagnosis through regular ANC in young PGs with or without mild to moderate anemia and with intervention if necessary is the key factor to avoid maternal and neonatal morbidity. The incidence of Rh negative blood group in antenatal women was 3% versus 6.34% observed previously. [13] The obstetric antenatal complications such as malpresentations, APH, IUGR, polyhydramnios, and postdate pregnancy requiring specialized supervision had similar rates in both groups. The infections such as dengue fever and typhoid observed in 7.3% with similar rates in both groups. These infections need to be diagnosed on time, treated appropriately and require specialized ANC. Antenatal BT was slightly more in the anemic group although not significant.

Iron deficiency anemia, a cause of considerable perinatal morbidity and mortality is most prevalent anemia affecting pregnant women, hence iron treatment was given to all women without diagnosing the cause of anemia. [14] In pregnancy, there is a state of physiological hemodilution following rise in plasma volume, with apparent fall in hemoglobin concentration in spite of the increase in hemoglobin mass. At the same time, there is negative iron balance. The normal value of hemoglobin at the time of first booking is not sufficient to rule out anemia since prevalence of anemia increases as pregnancy progresses. [15]

There was no significant association of anemia (Hb 8-10.9 gm%), with gestational age at delivery, mode of delivery, rate of instrumental deliveries. The overall LSCS rate of 26.8% with fetal distress the most common indication in 52.3% is comparable to a previous Indian ICMR study with LSCS rate of 25.4%. In the ICMR study, however, LSCS in PGs in that study was 42.4% and fetal distress the indication in 33.4%. [16] Anemia with Hb 8-10.9 gm% was not associated with an increase in preterm delivery compared to reported increased risk for preterm PROM in women Hb values ≤5 g/dl. [17] This study observed the preterm and instrumental vaginal delivery rate as 12.2%, and 11.9% respectively compared to 15.9%, and 3.2% respectively in a three review on pregnancy outcome in PGs in a tertiary Hospital. In this review, overall LSCS rate was 43.2% compared to 26.85 in this study. [18]

Anemia in pregnancy has been reported to be associated with an elevated risk LBW and small for gestational age (SGA), and the risk increased with the severity of anemia. [19] Our study had the incidence of IUGR and LBW as 6.7%, and 28.3% respectively with no statistically significant association with anemia (Hb 8-10.9 gm%). Another study also opined that moderate to severe, but not mild; maternal anemia appears to have an association with SGA outcomes, but the findings have to viewed with caution due to the great heterogeneity of the studies. [20] Our results indicate that the risks of preterm delivery and LBW are not increased in women with Hb 8-10.9 gm% but increases in proportion to the severity of maternal anemia as also reported before. [19],[21]

The LBW incidence of 28.3% is similar to 26% reported incidence in India. The current study showed neonatal morbidity in 17.4% and 39 NICU admissions (11.9%) and the rest were managed effectively without admissions. There was no difference in two groups with respect to NICU admissions. The availability of NICU is very important, since in this study 11.9% newborns of women with no high-risk factor except for anemia (Hb 8-10.9 gm%) required it. There is a severe shortage of fully fledged NICUs even in government medical colleges. There is a need to formulate selection criteria guidelines for admission to NICUs, increase availability of this special care to those who really need it. [22]

The immediate postpartum period required specialized care in 7.6% women and the mild to moderately anemic pregnant women were observed to have more postpartum adverse events like wound infection, PPH compared to those with no anemia. The incidence of PPH in this study was 2.1% less than reported 6% in a previous Indian study on low-risk pregnancies. [23] Women with anemia in the antenatal period were more prone to PPH (7/149 vs. 2/179; P = 0.085). BT, one of the skilled management therapies of anemia, is hallmark of good obstetric practice and was required in a total of 4.6% women, and significantly more in mild to moderate anemic women and the majority of BTs were in the postpartum period. The postpartum period, especially in anemic women has to have a cautious approach.

In the current study, there was one accidental maternal death, no fresh stillbirth, and two neonatal deaths. The rates are less than the national figures. This was because of the rigorous exclusion of high-risk pregnancies at the time of enrollment and also because of antenatal surveillance of the tertiary center.

Evidence shows that mild anemia has comparative maternal and perinatal outcome as nonanemic pregnant women. [24],[25] This study has added to the evidence that pregnant women with hemoglobin between 8 and 10 gm% had a comparable outcome with respect to LBW babies, operative deliveries, prolonged labor, and maternal outcome. The postpartum period, however, in the mild to moderate anemic groups needs careful supervision.

The strength of the study is involving the use of observation to answer the research questions; there was no bias, analytical techniques were used to gain maximum meaning, the women were followed up to the postpartum period, and the perinatal outcome was studied. One of the limitations was lost to follow-up (15.2%) was high, and the results need to be interpreted with caution.


   Conclusions Top


The mild to moderate anemic pregnant women can have a similar outcome as a normal pregnancy if anemia detected early in pregnancy and appropriate care is given. The detection of anemia and its effective treatment early in pregnancy available and affordable in most health care settings is a very cost-effective health care intervention to avoid maternal and perinatal morbidity. The postpartum period, however, needs careful supervision and intervention in mild to moderately anemic women since prone to adverse events in the postpartum period despite iron prophylaxis and treatment in the antenatal period.

Acknowledgment

The present study is a part of ICMR Task Force Study, and authors would like to acknowledge the valuable contributions of Mr. Arun Kumar, Prof. Suneeta Mittal and Dr. V. L. Jindal (AIIMS) and Dr. Nomita Chandhiok (ICMR).

Financial support and sponsorship

Indian Council of Medical Research, New Delhi - 110 029, India.

Conflicts of interest

There are no conflicts of interest.

 
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    Figures

  [Figure 1]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]


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