From: Seroprevalence of hepatitis B surface antigenemia and its effects on hematological parameters in pregnant women in Osogbo, Nigeria
HBsAg
Gestational age
Total
1st trimester
2nd trimester
3rd trimester
Positive
1
11
21
33
(20%)
(14.9%)
(17.4%)
(16.5%)
Negative
4
63
100
167
(80%)
(85.1%)
(82.6%)
(83.5%)
5
74
121
200