Table 1 General characteristics of the study population

Maternal age (years)

27 (24; 30)

26 (24; 30)

27 (25; 30)

0.5

Maternal height (centimeters)

156(153; 160)

156 (152; 160)

156 (153; 161)

32.1

Maternal weight (Kg)

65 (57; 75)

66.0 (57; 75)

66.0 (54.5; 75.5)

30.3

Parity

2(0; 3)

1 (0; 3)

3 (0; 4)

1.6

Number of previous fetal loss

0 (0; 1)

0 (0; 1)

0 (0; 1)

1.8

Number of previous caesarean section

0 (0; 0)

0 (0; 0)

0 (0; 0)

9.0

Maternal comorbidity

0 (0; 0)

0 (0; 0)

0 (0; 0)

1.5

Birth weight (Kg)

3.1 (2.7; 3.4)

3.1 (2.8; 3.4)

2.8 (2.0; 3.2)

4.1

Gestational age at birth (days)

265 (137; 276)

266 (137; 276)

225 (140; 254)

30.8

Maternal education (Educated)

3,284 [63.8]

3,171 [96.6]

113 [3.4]

26.0

Maternal education (Not educated)

1,866 [36.2]

1,747 [96.6]

119 [6.4]

Male infant

3,506 [51.4]

3,287 [93.6]

219 [6.3]

2.0

Female infant

3,310 [48.6]

3,113 [94.0]

197 [6.0]

Bleeding in pregnancy (Yes)

341 [5.1]

220 [64.5]

121 [35.5]

3.0

Bleeding in pregnancy (No)

6,406 [94.9]

6,107 [95.3]

299 [4.8]

Maternal occupation

16.2

 Not employed

2,894 [49.6]

2,650 [91.6]

244 [8.4]

 Self-employed

1,969 [33.8]

1,884 [95.7]

85 [4.3]

 Private/public employee

968 [16.7]

930 [96.1]

38 [3.9]

Ethnicity

7.7

 Nupe

4,611 [71.9]

4,297 [93.2]

314 [6.8]

 Hausa / Fulani

246 [3.8]

220 [89.4]

26 [10.6]

 Yoruba

790 [12.3]

758 [95.9]

32 [4.1]

 Igbo

395 [6.2]

378 [95.7]

17 [4.3]

 Gwari

19 [0.3]

17 [89.5]

2 [10.5]

 Others

356 [5.6]

342 [96.1]

14 [3.9]

Place of residence (Urban)

5,707 [89.1]

5,449 [95.5]

258 [4.5]

7.9

Place of residence (Rural)

700 [10.9]

552 [78.9]

148 [21.1]

Multiple gestation

<0.01

 Singleton

6,201 [89.2]

5,813 [93.7]

388 [6.3]

 Twins

719 [10.3]

665 [92.5]

54 [7.5]

 Triplets

35 [0.5]

34 [97.1]

1[2.86]

Fetal presentation

<0.01

 Cephalic

6,506 [93.7]

6,159 [94.7]

347 [5.3]

 Breech

334[4.8]

280 [83.8]

54 [16.2]

 Others

100[1.4]

62 [62.0]

38 [38.0]