A few weeks ago, Pres Oaks said the quiet part out loud about why they reduced the age of sister missionaries. During an interview with the Church owned Desert News, he made the following statement.
“In the time that we have lowered the age for young men and for young women in the past, we’ve seen an increase in people who meet someone in the mission field and marry them, which is perfectly appropriate if it doesn’t start too early in their missionary service.”
Having been on a mission, I can truly say WTF! Lets start with a little background. When I went on my mission in 1976, males could leave at 19, and females at 21. At this time, women were not encouraged to go on missions, so it was assumed but not explicitly stated that the age of 21 was so that if the young woman was not married, then they could go. Another reason assumed for the age gap was so that the Elders would not be attracted to the “much older” sisters. While just two years does not sound like a lot, I can assure you as new 19 year old missionaries, that the Sisters in our district at the LTM seemed like old ladies (no offence Hermana McMurtry!).
In October of 2012, President Thomas S. Monson announced a major change lowering the ages to 18 for men and 19 for women. This set off a frenzy of young women going on missions. But there was still an age difference, but only a year. During the press conference announcing the change, Elder Holland said that there was value in the year difference.
Now, some will ask why the difference in ages for young men and women. My friends, please. We have had a lot of experience in full-time missionary service and we have learned there is value in having at least some separation between the ages of the men and women who are serving and it works best when the sisters rather than the elders are the older.
Elder Holland during 2012 press conference
Elder Holland didn’t say what that value was., but again it was assumed that it was to keep the Elders from hooking up with the Sisters in the mission. (I’m told by my kids that “hooking up” can mean different things, but in my context it is just getting together, although the other meaning could also apply!). But the one year didn’t seems to make a whole lot of sense.
Then in November 2025, it was announced that young women could leave at 18 also. Why the change? Elder Holland is dead, so maybe the “value” is gone? Pres Oaks answered above. So that more Elders and Sisters would hook up ( get your mind out of the gutter) and come home as couples!
Counter Oak’s words to then Elder Kimble’s talk in 1968 (emphasis mine):
So, can I impress that again? LOCK YOUR HEARTS and leave the key at home! Wherever you live, leave the key home with your folks. And your heart – it’s only that part of it that deals with people generally that you open up. We just can’t tolerate it, can we? We can’t individually; we can’t totally. Someone said, “Well, is there any harm to marry a Mexican girl if you are working in Mexico! “No, that isn’t any crime, but it proves that some missionary has had his heart open! He has unlocked it! Is it wrong to marry a German girl when you have been on a German mission? Why no, there is no crime in that, if you met her some other way. But when you meet her in the mission field and you have opened your heart, I tell you it isn’t right, and you have shortchanged your mission! Just keep your hearts locked. Your whole thought should be missionary work. How can I make it more plain and more important than that? I’d like to because there is no reason whatever for any missionary to ever become involved, not even in a decent way, with any girl in the mission field. It isn’t the place! You guaranteed, you promised!
While I was not subject to this talk during my mission, I have heard from others that it was required reading during their missions. What I was subject to was a final interview by my mission president where he point blank asked me if I had fallen in love with a girl on my mission. The point being this was bad, and he wanted to nip it in the bud before I left the following day. Now during this time the main worry was falling in love with a local girl. The two year age gap between Sisters and Elders was doing its job very well.
So why do you think this change was made? I think the leaders have seen the later ages for marriage in the population generally transfer to the LDS members, thus delaying child birth, and hence reducing the number of children members are having. Children of record (baptisms of 8-year-old children of members) in the LDS Church have generally trended downward over the last 20 years, falling from over 100,000 annually in the early 2000s to roughly 91,000–94,000 by 2023–2024, reflecting lower birthrates. This decline is sharpest when compared to the 124,000 reported in 1982.
Pres Oaks in the interview cited above did admit that this lower of the age was “part of the Lord’s plan to overcome the tendency of waiting until the late 20s to have a first marriage,”. First marriage? Is this a tacit admission that early marriages have a higher rate of will divorce and thus the need for a second marriage?
If you served a mission, did you get the “Lock Your Heart” talk?
Did any of the missionaries in your mission get together after their mission?
Did any missionaries come back and marry a local person?
Do you think “speed dating” is coming to Zone Conferences anytime soon?
(BTW, AI killed it on making the photo above!)
Wheat & Tares 
Oh man, “Lock Your Heart!” I’d plumb forgotten about that talk, but it was indeed still required reading for incoming missionaries when I served in the early-2000s. Thanks for the Proustian reverie!
And yes, talk about mixed messages! Someone is going to get pregnant in the mission field sometime soon, and the First Presidency will have no one to blame but themselves.
Yes, “lock your heart” was one of thr missionary mantras when I served. Few missionaries violated that in practice. My son’s generation, (immediately pre-covid) was completely different. Nearly 20% of his colleagues “hooked up” with someone they met on their missions. They read “lock your heart” in the MTC, then ignored it completely in the field, especially when it comes to fellow missionaries. Mission presidents I know are now thrilled when couples meet in their missions, and happily attend receptions.
“Lock your heart” was required reading in our mission. With renewed emphasis after an Elder in my zone had a fling with one of the local woman, who was slightly older than him.
At least one Elder and Sister who met in our mission married later, but this fefinitely was frowned upon.
So I guess this is one more thing that in ten years, the church will be saying, “Oh we never taught that, it was just some MPs opinion…” like so many other “truths” that have seen a quiet 180 reversal.
At least the “don’t date the local girls” part of the “lock your hearts” policy obviously arose as a defense against the historical trope during the polygamy era that Mormon Elders were really sent on missions to recruit young women as polygamous brides.
In terms of DHO’s reversal of the policy as an attempt to get more marriages, I personally find it almost criminal the amount of pressure put on kids (and I use that word specifically) at BYU and in the Mormon corridor generally to marry extremely young and to have babies immediately. It was bad in my day (imagine thinking a 21 yo young women was an old maid!), but it has gotten even worse with the mission ages for boys being lowered. But totally in keeping with DHO’s MO. So many bad outcomes from this pressure to marry and reproduce young.
“Age at first marriage” is a data point tracked in surveys such as the US census. I think DHO is looking at statistical reports and getting upset about demographic trends. It’s not an implication of more divorces. He seems to be trying to lower the statistical age at first marriage by changing the mission age and trying to get teenagers to “hook up” to use OP’s words. What could possibly go wrong? He’s also trying to get people to have more babies by lecturing them which just seems out of touch, at least to me.