Table 2. Open in new tab Sexual Activity...

Variable	Nonpregnant/Nonpostpartum Periods^a	Early Pregnancy	Late Pregnancy	Postpartum Period
Total sex acts reported with study partner, no.	256462	7548		7205		3573
Total condomless sex acts reported with study partner, no.	25946	1530		947		327
Total person-months during follow-up, no.	55504	1602		2224		1541
Sex acts with study partner
No./person-month (95% CI)	4.62 (4.60–4.64)	4.71 (4.61–4.82)		3.24 (3.17–3.32)		2.32 (2.24–2.40)
RR for the mean frequency
Crude (95% CI)	1.00	1.11 (1.01–1.21)	.02	0.70 (0.63–0.78)	<.0001	0.48 (0.42–0.55)	<.0001
Adjusted^{^b} (95% CI)	1.00	1.04 (0.95–1.14)	.40	0.66 (0.59–0.73)	<.0001	0.45 (0.39–0.51)	<.0001
Condomless sex acts with study partner
No./person-month (95% CI)	0.47 (0.46–0.47)	0.96 (0.91–1.00)		0.43 (0.40–0.45)		0.21 (0.19–0.24)
RR for the mean frequency
Crude (95% CI)	1.00	2.64 (2.10–3.31)	<.0001	0.97 (0.70–1.32)	.83	0.55 (0.29–1.04)	.07
Adjusted^b (95% CI)	1.00	2.43 (1.91–3.10)	<.0001	0.91 (0.66–1.25)	.55	0.51 (0.27–0.97)	.04

Variable

Nonpregnant/Nonpostpartum Periods^a

Early Pregnancy

Late Pregnancy

Postpartum Period

Value

Total sex acts reported with study partner, no.

256462

7548

7205

3573

Total condomless sex acts reported with study partner, no.

25946

1530

947

327

Total person-months during follow-up, no.

55504

1602

2224

1541

Sex acts with study partner

No./person-month (95% CI)

4.62 (4.60–4.64)

4.71 (4.61–4.82)

3.24 (3.17–3.32)

2.32 (2.24–2.40)

RR for the mean frequency

Crude (95% CI)

1.00

1.11 (1.01–1.21)

.02

0.70 (0.63–0.78)

<.0001

0.48 (0.42–0.55)

<.0001

Adjusted^{^b} (95% CI)

1.00

1.04 (0.95–1.14)

.40

0.66 (0.59–0.73)

<.0001

0.45 (0.39–0.51)

<.0001

Condomless sex acts with study partner

No./person-month (95% CI)

0.47 (0.46–0.47)

0.96 (0.91–1.00)

0.43 (0.40–0.45)

0.21 (0.19–0.24)

RR for the mean frequency

Crude (95% CI)

1.00

2.64 (2.10–3.31)

<.0001

0.97 (0.70–1.32)

.83

0.55 (0.29–1.04)

.07

Adjusted^b (95% CI)

1.00

2.43 (1.91–3.10)

<.0001

0.91 (0.66–1.25)

.55

0.51 (0.27–0.97)

.04

Variable	Nonpregnant/Nonpostpartum Periods^a	Early Pregnancy	Late Pregnancy	Postpartum Period
Total sex acts reported with study partner, no.	256462	7548		7205		3573
Total condomless sex acts reported with study partner, no.	25946	1530		947		327
Total person-months during follow-up, no.	55504	1602		2224		1541
Sex acts with study partner
No./person-month (95% CI)	4.62 (4.60–4.64)	4.71 (4.61–4.82)		3.24 (3.17–3.32)		2.32 (2.24–2.40)
RR for the mean frequency
Crude (95% CI)	1.00	1.11 (1.01–1.21)	.02	0.70 (0.63–0.78)	<.0001	0.48 (0.42–0.55)	<.0001
Adjusted^{^b} (95% CI)	1.00	1.04 (0.95–1.14)	.40	0.66 (0.59–0.73)	<.0001	0.45 (0.39–0.51)	<.0001
Condomless sex acts with study partner
No./person-month (95% CI)	0.47 (0.46–0.47)	0.96 (0.91–1.00)		0.43 (0.40–0.45)		0.21 (0.19–0.24)
RR for the mean frequency
Crude (95% CI)	1.00	2.64 (2.10–3.31)	<.0001	0.97 (0.70–1.32)	.83	0.55 (0.29–1.04)	.07
Adjusted^b (95% CI)	1.00	2.43 (1.91–3.10)	<.0001	0.91 (0.66–1.25)	.55	0.51 (0.27–0.97)	.04

Table 2.

Open in new tab

Sexual Activity During Study Follow-up Among 2751 African Heterosexual HIV-Serodiscordant Couples With an Initially HIV-Uninfected Female Partner, by Reproductive Stage

Variable	Nonpregnant/Nonpostpartum Periods^a	Early Pregnancy		Late Pregnancy		Postpartum Period
Variable	Nonpregnant/Nonpostpartum Periods^a	Value	P	Value	P	Value	P
Total sex acts reported with study partner, no.	256462	7548		7205		3573
Total condomless sex acts reported with study partner, no.	25946	1530		947		327
Total person-months during follow-up, no.	55504	1602		2224		1541
Sex acts with study partner
No./person-month (95% CI)	4.62 (4.60–4.64)	4.71 (4.61–4.82)		3.24 (3.17–3.32)		2.32 (2.24–2.40)
RR for the mean frequency
Crude (95% CI)	1.00	1.11 (1.01–1.21)	.02	0.70 (0.63–0.78)	<.0001	0.48 (0.42–0.55)	<.0001
Adjusted^{^b} (95% CI)	1.00	1.04 (0.95–1.14)	.40	0.66 (0.59–0.73)	<.0001	0.45 (0.39–0.51)	<.0001
Condomless sex acts with study partner
No./person-month (95% CI)	0.47 (0.46–0.47)	0.96 (0.91–1.00)		0.43 (0.40–0.45)		0.21 (0.19–0.24)
RR for the mean frequency
Crude (95% CI)	1.00	2.64 (2.10–3.31)	<.0001	0.97 (0.70–1.32)	.83	0.55 (0.29–1.04)	.07
Adjusted^b (95% CI)	1.00	2.43 (1.91–3.10)	<.0001	0.91 (0.66–1.25)	.55	0.51 (0.27–0.97)	.04

Variable	Nonpregnant/Nonpostpartum Periods^a	Early Pregnancy		Late Pregnancy		Postpartum Period
Variable	Nonpregnant/Nonpostpartum Periods^a	Value	P	Value	P	Value	P
Total sex acts reported with study partner, no.	256462	7548		7205		3573
Total condomless sex acts reported with study partner, no.	25946	1530		947		327
Total person-months during follow-up, no.	55504	1602		2224		1541
Sex acts with study partner
No./person-month (95% CI)	4.62 (4.60–4.64)	4.71 (4.61–4.82)		3.24 (3.17–3.32)		2.32 (2.24–2.40)
RR for the mean frequency
Crude (95% CI)	1.00	1.11 (1.01–1.21)	.02	0.70 (0.63–0.78)	<.0001	0.48 (0.42–0.55)	<.0001
Adjusted^{^b} (95% CI)	1.00	1.04 (0.95–1.14)	.40	0.66 (0.59–0.73)	<.0001	0.45 (0.39–0.51)	<.0001
Condomless sex acts with study partner
No./person-month (95% CI)	0.47 (0.46–0.47)	0.96 (0.91–1.00)		0.43 (0.40–0.45)		0.21 (0.19–0.24)
RR for the mean frequency
Crude (95% CI)	1.00	2.64 (2.10–3.31)	<.0001	0.97 (0.70–1.32)	.83	0.55 (0.29–1.04)	.07
Adjusted^b (95% CI)	1.00	2.43 (1.91–3.10)	<.0001	0.91 (0.66–1.25)	.55	0.51 (0.27–0.97)	.04

Early pregnancy was defined as the interval from the start of pregnancy (typically the time of the last menstrual period) to gestation week 13. Late pregnancy was defined as the interval from gestation week 14 to the end of pregnancy. The postpartum period was defined as the interval from the end of pregnancy to month 6 after delivery (for women with live births), week 6 after pregnancy loss (for women with pregnancy loss at gestation week ≥20 or newborn death), or week 4 after pregnancy loss (for women with pregnancy loss during gestation weeks 6–19).

Abbreviations: CI, confidence interval; RR, relative risk.

^aReference group for comparisons is time spent during the nonpregnant and nonpostpartum periods.

^bAdjusted for female age and duration of relationship with HIV-infected study partner.

This Feature Is Available To Subscribers Only