Magnitude and factors associated with anemia among pregnant women attending antenatal care in public health centers in central zone of Tigray region, northern Ethiopia: a cross sectional study

Facility based cross sectional study design was conducted.

The study was conducted in central zone of Tigray region, Northern Ethiopia from November 1/2017 to January 30/2018. Central zone of Tigray is one of the six zones found in Tigray region. According to the 2007 census, Central zone of Tigray has 12 districts with estimated population of 1,500,000. Out of these population 750,000 are females and 750,000 are males. Central zone of Tigray has 66 health facilities (one referral hospital, 3 general hospitals, 6 primary hospitals and 56 health centers). The antenatal care (ANC) coverage of zone administration is 90%.

All pregnant women who attend ANC in public health centers in central zone of Tigray region during the study period.

All pregnant women who attend ANC at randomly selected public health centers in central zone of Tigray region during the study period.

The sample size was calculated using single proportion formula using epinfo-7 from study conducted in north west Ethiopia where the proportion of women with anemia was 25.2% [12].

Therefore, the total sample size was calculated using the assumption of marginal error 0.05, and 95% confidence interval. Based on these assumptions, the sample size was estimated as 290. After multiplying by 2 for design effect and adding 10% of non-respondents, the final sample size was determined as 638 study subjects.

Stratified multi stage sampling method was used to select health centers found in the central zone of Tigray region. During the selection of health centers, we stratified them as rural and urban. Two health centers each were randomly selected from 3 randomly selected woreda and one health center from urban in the central zone were included in the study. Proportion to sample size allocation was used to allocate the number of pregnant women from each health facilities by taking 3 months case load pregnant women on ANC visit. Systematic random sampling technique was used to get the study units.

The data was collected through interviewing the pregnant women face to face after getting informed consent using structured and pre-tested questionnaire. The questionnaire was originally developed in English and then translate into Tigrigna (local language). Later on it was translated back to English to ensure its consistency. Finally, it was prepared in Local language (Tigrigna language) to collect data. In addition to that chart review was conducted to extract hemoglobin level at ANC 1st visit and another necessary data from ANC longitudinal register. During data collection, two BSC Degree and 7 diploma holder in nursing were hired as supervisors and data collectors respectively.

Three days intensive training were given to data collectors and supervisors on the data collection tools and collection procedures by the principal investigator.

Daily supervision of data collectors were made at each health centers during the study period by the supervisors and principal investigator. The collected data were carefully checked for completeness and consistency. Any confusion on the data collection procedure and responses were handled timely.

A total of 634 pregnant women were interviewed with the response rate of 99%. The average mean age of study participants was 26.99 years with standard deviation (SD) of 5.99. The majority of age group belongs to 20–34 years which accounts 487(76.81%). Nearly all 609(96.06%) of study participants were with orthodox religion. Regarding to marital status, 13(2.05%) of study participants were not married whereas 552(87.07%) were married. Eighty five (13.41%) of participants were with housewife occupation and 277(43.69%) of the study participants were with primary educational level. Four hundred fifteen (65.46%) of the study participant’s household size were 1–4 and about a quarter of study participants 127(25.08%) were with second wealth quintile (Table 1).

Out of the total study participants, 175(27.6%) were nulliparous and 79(16.92%) had history of abortion. Fifty seven (12.42%) and 37(8.06%) of the study participants were with less than 2 years birth interval and had history of still birth respectively. Regarding to history of malaria attack 1 year prior to this study period, 112(17.67%) of the study subjects had history of malaria. Most of the participants 542(85.49%) and 582(91.8%) had no history of excessive menstrual bleeding and pregnancy related complications respectively. Only 132(20.82%) of study subjects were with planned pregnancy. Almost half 315(49.68%) of the participants were with MUAC less than 23 cm.

The magnitude of anemia (hemoglobin level < 11 mg/dl) were found that 16.88% (95% CI: 13.95%, 19.8%). The mean hemoglobin level of study participants were 12.3 (SD ± 1.33). Most of the pregnant women 489 (77.13%) who attend their first ANC were at the 3–6 months of gestational age (Table 2).

The meal frequency of study participants with greater than three times per day were 252(39.75%). Majority 541(85.33%) of the total participants were reported that they consume food made from cereals and grains daily. Besides, 179(28.23%) of the total participants didn’t take tea or coffee. Concerning to fruit and green leafy vegetables intake, only 11(1.74%) and 40(6.31%) of the total study participants reported with daily intake respectively (Table 3).

Socio-demographic factors like; age of women, religion, marital status, occupation, household size and wealth quintile were not significantly associated with the anemia in Bivariable analysis at P-value < 0.05. Similarly, parity of women, history of abortion, birth interval, history of still birth and nutritional status were not significantly associated with anemia in Bivariable analysis. Regarding to dietary intake, variables which were not significantly associated with anemia in Bivariable analysis at P-value < 0.05 were; eating food made from cereals and grains, drinking tea or coffee, fruit intake, green leafy vegetables intake, dairy products/ milk product intake, meat intake and egg intake.

Variables which were significantly associated with anemia in Bivariable analysis but remains insignificant in multivariable analysis were; women’s level of education, birth interval and had pregnancy related complication. However, history of malaria attack 1 year prior to study period, women who had history of excessive menstrual bleeding, planned pregnancy and meal frequency were significantly associated with anemia in the multivariable analysis. Women with history of malaria attack were significantly associated with anemia comparing to women who had no malaria attack (AOR = 4.73, 95% CI: 2.64, 8.46). Comparing to women who had no history of excessive menstrual bleeding, anemia was 3.94 times higher in women with history of excessive menstrual bleeding (AOR = 394, 95% CI: 2.11, 7.35). Similarly anemia was higher in pregnant women who had no pregnancy planning (AOR = 2.5, 95% CI: 1.4, 4.42) comparing to their counter parts. Meal frequency less than or equal to 3 times per day was also significantly associated with anemia (AOR = 1.89, 95% CI: 1.02, 3.5) (Table 4).