Preparing linked population data for research: cohort study of prisoner perinatal health outcomes

Table 3 Number of maternities with a pregnancy incarceration, pregnant prisoners and prisoner controls

	Timing of incarceration(s) relative to pregnancy	Pregnant prisoners^a			Prisoner controls^b			Total
	Timing of incarceration(s) relative to pregnancy	Birth out of prison	Birth in prison	Total	Own controls^c	Peer controls	Total	Total
Prison maternities	During	166	31	197	…	…	…	197
	Before and during	67	9	76	185	1,394	1,579	1,655
	After and during	102	44	146	134	1,215	1,349	1,495
	Before during and after	134	44	178	80	291	371	549
	Total	469	128	597	399	2,900	3,299	3,896
Prisoner mothers	During pregnancy	166	31	197	(113)	–	–	197
	Before and during	67	9	76	(45)	1,065	1,065	1,141
	After and during	96	36	132	(63)	746	746	878
	Before during and after	116	37	153	(65)	220	220	373
	Total	445	113	558	(286)	2,031	2,031	2,589

Notes:
a Pregnant prisoners have at least one maternity with an incarceration episode during pregnancy. Prisoner mothers can have more than one prison maternity or both prison and non-prison maternities
b Contemporaneous maternities among women incarcerated between 1998 and 2006, but not during pregnancy
c Own control prisoner mothers have both a maternities with pregnancy incarceration and maternity with pregnancy wholly in the community. These prisoner mothers have already been counted with pregnant prisoners
– not applicable () numbers in brackets do not contribute to row total

ISSN: 1471-2288