Being born preterm or with low weight implies a risk of infertility and premature loss of ovarian function; a national register study

Figures & data

Table 1. Socio-demographic and birth characteristics of the study population by the presence of primary ovarian insufficiency (primary ovarian insufficiency, n = 18,627).

	No primary ovarian insufficiency		Primary ovarian insufficiency
	n	%	n	%	p-value
Year of birth					<0.001
1973–1975	235,118	23.2	7977	42.8
1978–1982	218,071	21.5	5050	27.1
1983–1987	226,642	22.3	3225	17.3
1988–1993	335,420	33.0	2375	12.8
Education					<0.001
Elementary	67,560	6.8	991	5.4
High school	442,870	44.9	6632	35.8
University	476,811	48.3	10,889	58.8
Missing	28,010	2.8	115	0.6
Gestational age					<0.001
Very preterm	4968	0.5	96	0.5
Preterm	45,996	4.5	864	4.6
Term	871,826	85.9	15,652	84.0
Post term	92,461	9.1	2015	10.8
Preterm birth					0.407
No	964,287	95.0	17,667	94.8
Yes	50,964	5.0	960	5.2
Birthweight					<0.001
Very low birthweight	4655	0.5	91	0.5
Low birthweight	38,557	3.8	783	4.2
Normal birthweight	972,039	95.7	17,753	95.3
Low birthweight					<0.001
No	972,039	95.7	17,753	95.3
Yes	43,212	4.3	874	4.7
Small for gestational age (1SD)					<0.001
No	808,140	79.6	14,354	77.1
Yes	207,111	20.4	4273	22.9
Small for gestational age (2SD)					<0.001
No	977,074	96.2	17,781	95.5
Yes	38,177	3.8	846	4.5
Small for gestational age (3SD)					0.006
No	1,009,542	99.4	18,494	99.3
Yes	5709	0.6	133	0.7
Large for gestational age (1SD)					<0.001
No	878,038	86.5	16,374	87.9
Yes	137,213	13.5	2253	12.1
Large for gestational age (2SD)					0.076
No	987,461	97.3	18,157	97.5
Yes	27,790	2.7	470	2.1
Large for gestational age (3SD)					0.436
No	1,010,548	99.5	18,548	99.6
Yes	4703	0.5	79	0.4
Delivery method					0.057
Normal	859,936	84.7	15,896	85.3
Instrumental	52,227	5.1	915	4.9
Section	103,088	10.2	1816	9.7

Table 2. Crude and adjusted odds ratios and corresponding 95% confidence intervals (CIs) of primary ovarian insufficiency among infants born with different characteristics.

	Crude OR	95% CI	p-Value	Adjusted OR^a	95% CI	p-value
Premature delivery (<37 gestational weeks)	1.03	0.96–1.12	0.407	1.11	1.04–1.19	0.001
Premature delivery, excluding SGA	1.00	0.93–1.07	0.997	1.08	1.01–1.16	0.037
Low birthweight (<2500 g)	1.11	1.03–1.19	0.004	1.15	1.07–1.23	<0.001
Low birthweight, excluding SGA	1.02	0.92–1.12	0.715	1.10	1.00–1.22	0.053
Small for gestational age (1SD)	1.16	1.12–1.20	<0.001	1.05	1.02–1.09	0.004
Small for gestational age (2SD)	1.22	1.14–1.31	<0.001	1.10	1.02–1.18	0.009
Small for gestational age (3SD)	1.27	1.07–1.51	0.006	1.16	1.07–1.38	0.095
Large for gestational age (1SD)	0.88	0.84–0.92	<0.001	0.95	0.91–1.00	0.036
Large for gestational age (2SD)	0.92	0.84–1.01	0.076	1.00	0.91–1.09	0.908
Large for gestational age (3SD)	0.92	0.73–1.14	0.436	0.96	0.76–1.20	0.707
SGA, excluding PT and LBW	1.22	1.11–1.35	<0.001	1.01	0.91–1.12	0.841
Preterm, excluding SGA and LBW	0.98	0.89–1.08	0.663	1.05	0.95–1.15	0.321
LBW, excluding SGA and preterm	0.97	0.75–1.24	0.803	1.03	0.80–1.32	0.843

^aAdjusted for year of birth and educational level.