ohoho
very interesting question
with cedfia + amberwood in mind...

cedric would be more likely to make a mistake in ensuring contraception, but he also really, REALLY doesn't want kids, so if he suspects sofia is preganant, (and she'd hide it from him, because she really, REALLY wants kids), he'd slip her an abortificient

amber and wormwood wouldn't have that sort of back and forth drama- if amber got pregnant before she was ready she'd easily abort

if this was intended as a purely horny question about fertility, i'd say amber. lorelei had fraternal twins, so amber has the genes for extra eggs