Table 1.

Mean^* maternal hCG levels by maternal characteristics and child sex in among 2,257 controls: Finnish Maternity Cohort

Characteristic	N	hCG (mlU/mL)	p
Age at first term birth (years)			0.08
<25 years	386	111,678
25–30 years	694	117,132
30–35 years	669	118,528
≥35 years	508	115,927
Maternal smoking			<0.01
Yes	292	95,301
No	1,900	119,489
Gravidity			0.47
Primigravid	1,606	116,641
Multigravid	600	115,192
Neonate sex			<0.01
Boy	1,118	111,820
Girl	1,132	120,708
Time to 2nd birth (years)			0.55
No additional pregnancy	750	114,560
<2 years	535	116,743
2–5 years	837	117,548
>5 years	130	116,615

^*Calculated using adjusted hCG; mean corresponds to concentrations at gestational day 73