Table 3.
Mean decline in log AMH levels over 13–15 years by reproductive factors (n=799), Nurses’ Health Study 2.
| Reproductive Factor | No. of Participants | MV1 | MV2 | MV3 | |||
|---|---|---|---|---|---|---|---|
|
| |||||||
| β | 95% CI | β | 95% CI | β | 95% CI | ||
|
| |||||||
| Parity | |||||||
| 0 | 114 | REF | -- | REF | -- | REF | -- |
| 1 | 146 | 0.44 | (0.11, 0.77) | 0.45 | (0.12, 0.79) | 0.45 | (0.10, 0.80) |
| 2 | 307 | 0.23 | (−0.06, 0.52) | 0.30 | (−0.002, 0.60) | 0.31 | (−0.02, 0.63) |
| ≥ 3 | 232 | 0.24 | (−0.06, 0.55) | 0.32 | (0.01, 0.64) | 0.33 | (−0.03, 0.70) |
| Per pregnancy | 0.02 | 0.04 | 0.04 | ||||
| p-trend = 0.65 | p-trend = 0.29 | p-trend = 0.42 | |||||
| Cumulative total breastfeeding duration (mo.) | |||||||
| 0 – <1 | 171 | REF | -- | REF | -- | REF | -- |
| 1 – 6 | 90 | 0.24 | (−0.10, 0.58) | 0.24 | (−0.10, 0.59) | 0.22 | (−0.14, 0.59) |
| 7 – 12 | 120 | 0.07 | (−0.24, 0.38) | 0.07 | (−0.25, 0.39) | 0.05 | (−0.30, 0.40) |
| 13 – 18 | 126 | 0.35 | (0.04, 0.66) | 0.44 | (0.12, 0.75) | 0.42 | (0.06, 0.77) |
| 19 – 24 | 84 | 0.08 | (−0.27, 0.43) | 0.10 | (−0.25, 0.46) | 0.07 | (−0.33, 0.48) |
| ≥25 | 203 | 0.08 | (−0.19, 0.36) | 0.17 | (−0.11, 0.46) | 0.14 | (−0.21, 0.49) |
| Per month | <.0.0001 | 0.002 | 0.0004 | ||||
| p-trend = 0.99 | p-trend = 0.48 | p-trend = 0.91 | |||||
| Cumulative exclusive breastfeeding duration (mo.) | |||||||
| 0 – <1 | 313 | REF | -- | REF | -- | REF | -- |
| 1 – 6 | 153 | −0.03 | (−0.29, 0.23) | −0.07 | (−0.33, 0.20) | −0.08 | (−0.35, 0.19) |
| 7 – 12 | 186 | 0.06 | (−0.18, 0.30) | 0.08 | (−0.17, 0.32) | 0.06 | (−0.20, 0.32) |
| 13 – 18 | 99 | 0.02 | (−0.28, 0.32) | 0.09 | (−0.22, 0.40) | 0.06 | (−0.27, 0.40) |
| ≥19 | 34 | 0.28 | (−0.19, 0.75) | 0.40 | (−0.09, 0.88) | 0.35 | (−0.18, 0.88) |
| Per month | 0.01 | 0.01 | 0.01 | ||||
| p-trend = 0.41 | p-trend = 0.16 | p-trend = 0.31 | |||||
MV1: adjusted for age at blood collection, assay (fasting status [dichotomous], time of blood collection [4 pm, 3 pm, 1–2pm, 5pm–12am], season of blood collection [winter, spring, fall, summer], luteal day [0–5, 6–9, 10–14, ≥15 days])), and AMH level at first blood collection
MV2: MV1 + further adjusted for pack-years of smoking (continuous), smoking status (never, current, former), BMI (continuous), exogenous hormone use (dichotomous), duration of oral contraceptive use (never, 1–23, 24–71, 72–119, ≥120 months), years until cycle became regular (never, <1, 1 – 2, 3 – 4, ≥5.0 years), infertility history (dichotomous), age at menarche (≤11, 12, ≥13 years), and alcohol intake (never, ≤6 drinks per week, 1 drink per day, ≥2 drinks per day)
MV3: MV2 + further adjusted for other reproductive factor: cumulative total breastfeeding duration (continuous) or parity (continuous)